Open work thermoplastic webs are known in the art. U.S. Pat. Nos. 3,386,876 and 3,539,666 represent examples of such webs. Usually such webs are made from a thermoplastic material containing a blowing agent. During a film blowing process, the blowing agent creates open cells which are further enlarged by stretching the film. The main deficiency of webs so formed is that it is necessary to use a blowing agent, which can pollute the atmosphere.
U.S. Pat. Nos. 4,728,698 and 4,835,047 disclosed reinforced thermoplastics in which microscopic fibers of a liquid crystal polymer (LCP), which are formed in situ in a matrix of a thermoplastic polymer, constitute the reinforcing agent. These fibers, which are less than 10 microns in diameter, are oriented predominantly in one direction. Fiber reinforced thermoplastics of this type and articles made therefrom exhibit excellent mechanical properties, such as tensile strength and modulus, in the direction of fiber orientation, but have lower strength and modulus values in the transverse or cross-direction.